Journal of Applied Polymer Science, Vol.90, No.8, 2246-2254, 2003
Effects of the chirality and functionality of monomers on the holographic gratings formed in photosensitive films
Photosensitive holographic polymer films were fabricated. Instead of liquid crystals, a nonreactive high-refractive-index diphenyl sulfide was mixed with several monomers and an initiator for the preparation of the holographic grating films. To investigate the formation of periodic arrays of the photosensitive refractive-index modulation films and the effects of the chirality and functionality of monomers on the diffraction efficiency, chiral monomeric (-)-bornyl acrylate, (+)-bornyl acrylate, and the racemate ()-bornyl acrylate were synthesized and copolymerized with various multifunctional monomers. A reasonable schematic of the photosensitive polymerization mechanism was proposed. The effects of the multifunctional monomers, initiator concentrations, and feed monomer concentrations on the diffraction efficiencies were investigated. The morphologies of the polymer matrices were studied with scanning electron microscopy. Pictures of real light diffraction patterns with 15 grating points were obtained. In comparison with those described in the literature, the diffraction efficiency obtained in this investigation was relatively high. (C) 2003 Wiley Periodicals, Inc.